861993501 has 16 divisors (see below), whose sum is σ = 1229653440. Its totient is φ = 535489920.

The previous prime is 861993439. The next prime is 861993521. The reversal of 861993501 is 105399168.

It is not a de Polignac number, because 861993501 - 2¹³ = 861985309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861993521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120480 + ... + 127433.

It is an arithmetic number, because the mean of its divisors is an integer number (76853340).

Almost surely, 2^861993501 is an apocalyptic number.

It is an amenable number.

861993501 is a deficient number, since it is larger than the sum of its proper divisors (367659939).

861993501 is a wasteful number, since it uses less digits than its factorization.

861993501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247996.

The product of its (nonzero) digits is 58320, while the sum is 42.

The square root of 861993501 is about 29359.7258331886. The cubic root of 861993501 is about 951.7027637159.

The spelling of 861993501 in words is "eight hundred sixty-one million, nine hundred ninety-three thousand, five hundred one".